org.apache.flink.streaming.api.functions.async.ResultFuture Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.streaming.api.functions.async;
import org.apache.flink.annotation.PublicEvolving;
import java.util.Collection;
/**
* {@link ResultFuture} collects data / error in user codes while processing async i/o.
*
* @param Output type
*/
@PublicEvolving
public interface ResultFuture {
/**
* Completes the result future with a collection of result objects.
*
* Note that it should be called for exactly one time in the user code.
* Calling this function for multiple times will cause data lose.
*
*
Put all results in a {@link Collection} and then emit output.
*
* @param result A list of results.
*/
void complete(Collection result);
/**
* Completes the result future exceptionally with an exception.
*
* @param error A Throwable object.
*/
void completeExceptionally(Throwable error);
}